Synthesia Talk

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The "Finger-based channel" key light mode (under Settings --> [your virtual MIDI port] --> Key Lights) is designed specifically to support this kind of thing. It'll take a little bit of adaptation of their Arduino code, but all of the upcoming-note information is nicely exposed using that setting.

You'll probably need some app that pretends to be a virtual MIDI device and can write to the Arduino's serial port. Or you could update the Arduino's boot loader to behave like a physical USB-MIDI device. (The Arduino-compatible Teensy boards have this built in and available just by changing a drop-down menu option. I know this because I just used one to do something rather similar.)

In any event, some programming will be involved somewhere -- either on the Arduino or computer side -- to get this up and running. Synthesia isn't compatible with that MuseScore feature out of the box.